Hi all, our car has a lot of over finch extras , and was thinking of having the over finch lettering rather than the range rover ... Is this a easy task to remove the old lettering and putting the overfinch on and where to buy the lettering ?

Old lettering off - yes an easy task
You'll need. A hair dryer, some fishing line or dental floss, a glue remover ( autoglym, petrol, wd40).
Heat the letters gently, then 'saw' behind them. Use the glue remover to take off any residual glue left behind.
I'd also give the area a quick polish as you'll have outlines of 'RANGE ROVER' there which will look odd when you put 'OVERFINCH' back on

New letters, I guess Overfinch or eBay  ON THE WAY: BMW F21 M140i
MERCEDES GL350 - Metallic Navy Blue w/Grey interior

GOING: BMW F31 335D MSport+ xDrive Touring
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Thanks you

I would get template to save time trying to measure each letter. 

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Yes that's an idea ! Just been thinking how Can I make
Sure it's all even

The Overfinch lettering *should* go straight over the original 'Range Rover' marks iirc.

10 letters range rover 9 overfinch ???? 

Supporting the London Air Ambulance with my Brothers

Ten points for paying attention.